Method for controlling a wind turbine

ABSTRACT

There is provided a method of controlling a wind turbine on starting or running up the wind turbine before the wind turbine is connected to an electrical supply grid or before the wind turbine is connected to the electrical energy supply grid again. The wind turbine has a rotor having a rotor arresting means, at least one rotor blade and at least one blade angle detection sensor for each rotor blade for detecting the blade angle of the rotor blade. The blade angle of the at least one rotor blade is detected by means of the blade angle detection sensor. Unlocking of the rotor arresting means is blocked until the detected at least one blade angle is within a predetermined angle range. In that way it is possible to ensure that the rotor arresting means is released only when the blades are for example in the feathered position.

BACKGROUND Technical Field

The present invention concerns a method of controlling a wind turbinewhen starting or running up the wind turbine, a mobile control unit anda wind turbine.

Description of the Related Art

In normal operation the wind turbine is connected to an electricalsupply grid and delivers electrical energy to the supply grid. Ifhowever there is no wind it can then happen that the wind turbine itselfdraws electrical energy from the energy supply grid to maintain turbineoperation.

In addition in construction the wind turbine is typically also not yetconnected to the electrical energy supply grid and therefore cannot takeenergy from the supply grid to control the wind turbine. A so-calledconstruction aid for example can be provided for controlling the windturbine while it is not connected to the electrical energy supply grid.That construction aid can have an electrical power supply and acontroller.

On the German patent application from which priority is claimed theGerman Patent and Trade Mark Office searched the following documents: EP2 905 467 A1, DE 10 2008 022 383 A1, DE 10 2010 039 628 A1, DE 2010 037695 A1, DE 10 2013 004 580 A1 and EP 2 963 287 A1.

BRIEF SUMMARY

Provided is a method of controlling a wind turbine on starting orrunning up the wind turbine before the wind turbine is connected to anelectrical supply grid.

Provided is a method of controlling a wind turbine on starting orrunning up the wind turbine before the wind turbine is connected to anelectrical supply grid or before the wind turbine is connected to theelectrical energy supply grid again. The wind turbine has a rotor havinga rotor arresting means, at least one rotor blade and at least one bladeangle detection sensor for each rotor blade for detecting the bladeangle of the rotor blade. The blade angle of the at least one rotorblade is detected by means of the blade angle detection sensor.Unlocking of the rotor arresting means is blocked until the detected atleast one blade angle is within a predetermined angle range. In that wayit is possible to ensure that the rotor arresting means is released onlywhen the blades are for example in the feathered position.

That makes it possible in particular to avoid a highly dangeroussituation when constructing a wind turbine if the rotor arresting meansis released and the wind turbine is not yet connected to the electricalsupply grid in order for example to be able to carry out a blade angleadjustment operation and the wind which is blowing at the time causesthe aerodynamic rotor (hub+rotor blades) to rotate without being braked.

According to an aspect of the present invention, the blade angledetection sensor can have inductive sensors and position gauges.Detection of the blade angle can however also be effected by way of anyother sensors.

Further configurations of the invention are subject-matter of theappendant claims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Advantages and embodiments by way of example of the invention aredescribed in greater detail hereinafter with reference to the drawing.

FIG. 1 shows a diagrammatic view of a wind turbine according to anaspect of the present invention,

FIGS. 2 and 3 each show a diagrammatic view of the functional groups ofa wind turbine according to a first embodiment of the invention, and

FIGS. 4 and 5 each show a diagrammatic view of the functional groups ofa wind turbine according to a second embodiment of the invention.

DETAILED DESCRIPTION

FIG. 1 shows a diagrammatic view of a wind turbine according to anaspect of the present invention. The wind turbine 100 has a tower 102with a nacelle 104 and an aerodynamic rotor 106. The aerodynamic rotor106 has at least one rotor blade 200, 201-203. The blade angle of therotor blades 200, 201-203 can be adjusted for example by means of apitch motor (not shown). The rotor 106 can be arrested by a rotorarresting device or means 300 such as the arresting device described inUS Pat. Pub. No. 2020/0088163, which is incorporated by referenceherein. Optionally there can be provided a rotor brake 400 which servesto be able to brake the aerodynamic rotor 106. FIGS. 2 and 3 each show adiagrammatic view of the functional groups of a wind turbine accordingto a first embodiment. FIG. 2 shows in particular the rotor blade 203.The rotor blade 203 has for example a blade angle of 90° and can bearranged in the 3 o'clock position. A blade angle detection sensor 600having for example two sensors 610 and two position gauges 620 can beprovided in the region of a rotor blade root of the blade 203. The othertwo rotor blades 201, 202 can also have a corresponding blade angledetection sensor 600. The information from the blade angle detectionsensors 600 of the three rotor blades 201-203 can be output to a bladeangle controller 500. The information in respect of the blade angles ofthe three rotor blades 200, 201-203 can be combined together in theblade angle controller 500. The combined information can be passed to aconstruction aid 700. The construction aid 700 can be used in particularwhen the wind turbine is being erected and the wind turbine is not yetconnected to the electrical energy supply grid. As an alternativethereto the construction aid 700 can be used after a service has beencarried out on the wind turbine and the wind turbine was separated fromthe supply grid.

Certain functions of the wind turbine 100 like for example blade angleadjustment can be controlled by means of the construction aid 700 whichrepresents a mobile controller. The brake 400 and the rotor arrestingmeans 300 can be connected to the mobile control unit 700 or the mobilecontroller 700 receives information in respect of operation of the brake400 and the rotor arresting means 300.

The sensors 110 can be for example in the form of a inductive sensors.

The rotor arresting means 300 can optionally have an electromagneticvalve 310 and a plurality of bolts 320 which can be introduced into orremoved from recesses 330 in the rotor in order to arrest or release therotor.

As an alternative thereto the rotor arresting means can also beimplemented in another way.

The mobile controller (construction aid) 700 is adapted, in particularwhen the wind turbine has been separated from the energy supply grid, toblock unlocking of the rotor arresting means until the mobile controller700 receives appropriate blade angle information from the controller500. In other words the rotor arresting means 300 is deactivated orunlocked only when the three rotor blades 201-203 are in a desiredposition, for example the feathered position. Together with the rotorarresting means 300 the brake 400 can also be released when thecontroller 500 notifies the mobile controller 700 that the blade anglesof the rotor blades 201-203 are in the desired position.

While the rotor blades in FIG. 2 are in the feathered position the rotorblades as shown in FIG. 3 are at a blade angle of less than 90°. In thatcase the blade angles of the three rotor blades 201-203 are not in thedesired range and the controller 500 passes that information to themobile controller 700 so that the rotor arresting means 300 and/or thebrake 400 cannot be released.

FIGS. 4 and 5 each show a diagrammatic view of the functional groups ofa wind turbine according to a second embodiment of the invention. Whilethe first embodiment relates to a mobile controller 700 the secondembodiment describes how the method according to the invention isimplemented with the fixed and central nacelle controller 800. In FIG. 4the rotor blade 203 is shown in the 90° position and thus the connectionbox/controller 500 can transmit an appropriate signal by way of a rotorsub-distribution and a slip ring transmitter 900 to a nacelle controller800. The nacelle controller 800 can be coupled to a stator unit 950which in turn can be coupled to a rotor brake 400 and the rotorarresting means 300. The brake 400 and the rotor arresting means 300respectively correspond to the brake 400 and the rotor arresting means300 of the first embodiment.

In FIG. 5 the rotor blade 203 is at a blade angle of less than 90° andis thus not in the feathered position. That corresponding informationrelating to the respective rotor blades 201-203 is output to thecontroller 500 which combines those items of information and passes themto the nacelle controller 800 by way of the rotor sub-distribution 106 aand the slip ring transmitter 900. In that case the stator unit 950 canrelease neither the rotor arresting means nor the brake 400 as the rotorblades 200 do not involve the desired blade angle.

1. A method of controlling a wind turbine, the method comprising:connecting a mobile controller to the wind turbine, the wind turbinehaving a rotor and a rotor arresting device, a rotor blade and a bladeangle detection sensor, activating the mobile controller activated whenstarting or running up the wind turbine before the wind turbine isconnected to an electrical supply grid or before the wind turbine isconnected to the electrical supply grid again, during which the windturbine cannot take energy from the energy supply grid for controllingthe wind turbine, detecting the blade angle of the rotor blade,outputting the detected blade angles to the mobile controller, andblocking an unlocking of a rotor arresting device using the mobilecontroller in response to the detected blade angle not being within apredetermined blade angle range.
 2. The method of controlling a windturbine according to claim 1 wherein the predetermined angle range ofthe rotor blade corresponds to a feathered position of the rotor blade.3. (canceled)
 4. A mobile controller for controlling a wind turbine,wherein the wind turbine has a central, controller, the mobilecontroller comprising: a first input configured to receive at least oneblade angle signal indicative of a blade angle of at least one rotorblade, and an output configured to control a rotor arresting devicemeans, wherein the mobile control unit is configured not to deactivatethe rotor arresting device as long as the blade angles of the at leastone rotor blade are not within a predetermined blade angle range.
 5. Amethod comprising: using a mobile controller to control a rotorarresting device of a wind turbine while the wind turbine is notconnected to an energy supply grid or during maintenance of the windturbine such that the wind turbine cannot receive energy from the energysupply grid for controlling the wind turbine, wherein the mobile controlunit is designed to receive blade angle information relating to one ormore rotor blades of the wind turbine and to control the rotor arrestingdevice in dependence on the received blade angle information and toprevent unlocking of the rotor arresting device as long as the bladeangles of the one or more rotor blades are outside a predetermined bladeangle range.
 6. A wind turbine, comprising: a rotor having at least onerotor blade and a rotor arresting device for arresting the rotor blade,the at least one rotor blade including a rotor blade root; at least oneblade angle detection sensor in a region of the rotor blade root of eachrotor blade for detecting a blade angle of the respective rotor blade,and a controller configured to control the rotor arresting means independence on blade angles of the rotor blades detected by the bladeangle detection sensors, wherein the controller is configured to controlthe rotor arresting means in dependence on the detected blade angles andto prevent unlocking of the rotor arresting means as long as thedetected at least one blade angle is not within a predetermined bladeangle range.